The Tata Tiago hatchback and the Tigor sedan will not offer the option of a diesel engine once the stringent BS-VI emission norms come into force from April 1, 2020. This is because the current 1.05-litre 3-cylinder diesel cannot be upgraded to meet the BS-VI emission norms.
Moreover, the carmaker feels that low demand for the diesel variants will not justify the high costs involved in developing a new small capacity diesel engine.
"Around 80 percent of the demand in this segment (Tiago and Tigor) is for the petrol variants and thus the additional investment required does not make a viable plan," Rajendra Petkar, Chief Technology Officer (CTO), Tata Motors, told Autocar India on the sidelines of the Geneva Motor show 2019.
During April-January 2019, the Tiago diesel accounted for just 14 percent of overall Tiago sales while the Tigor diesel accounted for 15 percent of total sales.
Tata Motors sold an average of 1114 units of the Tiago diesel and 6606 units of the petrol variant during the period. Average monthly sales of the Tigor diesel were 360 units and those of the petrol were 1940 units.
The fast approaching April 1, 2020 deadline for the stricter emission norms will see many carmakers discontinuing smaller diesels from their line-up. However, automakers are likely to continue to offer a diesels option on mid size cars and SUVs.
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